You need to provide more information. Some contracts are simple contracts that will take less than an hour to draft, while others are complex and may take 20 or 30 hours or more. What type of contract are you inquiring about? Also, attorneys' hourly fees will vary quite a bit, but many attorneys charge in the range of $200 to $500 per hour. Some attorneys may agree to provide a service (such as drafting a contract) for a flat fee, depending on the type of contract involved.
The cost varies greatly depending on complexity. Some contracts require research into regulatory matters to make certain the contract is compliant. You should also consider that the cost of negotiation and revisions would be part of the overall investment.
There's no average. It depends on your market in your city, the lawyer (solo, small firm or big firm) and the type of contract (40 page distribution contract, 3 page joint venture, 1 page assignment of rights, etc. etc., etc.).
Shop your situation to different lawyers with some specific details.
I'm only licensed in CA. Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.